Honestly, mastering professionals sitting behind tens of thousands of dollars worth of equipment know what they're doing.
In defense of e.q.-ing sometimes:
I own a rather unforgiving set of very neutral speakers that would be considered high-end.
There are recordings that have extremely low volumes at low frequencies.
It could be that they are mixed and mastered for cheap radios in the old days, could be that it was not mixed in an expensive studio, and the monitor speakers had too much bass.
Also, I have some modern recordings that are of a great sound quality, but have a bass that is so extremely loud in some specific low frequency that it scares even me. (and I like bass)
That is probably because the room or the speakers originally used for mixing didn't reveal those specific low frequencies.
Also, many speakers and headphones (especially in the lower price range) won't have a flat frequency response, can sound boomy, have exaggerated highs, etc. It's perfectly valid to try and make those sound a little bit more pleasant by using some e.q.-ing.
And, at low volume levels, the human ear is far less sensitive for low and high frequencies.
That's also why the (often mis-used) 'loudness button' was invented...
So, while I do agree that you should always try to get (your ears) used to listen to music without fiddling with e.q., there are some very valid reasons to use them.
At the O.P.:
But be sure that when in MusicBee you increase some sliders, also make sure that you lower the pre-amp slider on the left with a substantial amount to prevent clipping or distortion.